TY - CONF A1 - Kossatz, Philipp A1 - Andresen, Elina A1 - Würth, Christian A1 - Frenzel, Florian A1 - Prinz, Carsten A1 - Resch-Genger, Ute T1 - Lanthanide Nanocrystals as Authentication and Security Tags and Reporters for Optical Sensors N2 - Counterfeiting of goods has serious economic implications worldwide and can present a considerable threat to human health and national security, rendering product authentication more and more important. This led to an increasing interest in simple tags for anticounterfeiting and authentication applications for the integration into different materials and matrices that are robust enough to survive the respective production processes and can be read out in-situ with simple instrumentation. Here we present a platform of chemically inert, multi-color luminescent lanthanide nanocrystals (LnNC) consisting of a NaYF4 matrix doped with Yb, Er, Tm, or Ho as promising candidates for such applications. LnNC with characteristic multi-color emission patterns, composed of narrow bands of varying intensity in the ultraviolet, visible, near-infrared, and short-wave were synthesized via a thermal decomposition approach under inert conditions[1]. The tailor-made design of different emission pattern was achieved by tuning particle size, material composition, and particle surface chemistry in upscaleable syntheses.[2] Particle size and morphology were determined by dynamic light scattering and transmission electron microscopy and the optical properties were characterized by absorption and fluorescence spectroscopy as well as fluorescence lifetime measurements. The particles were then incorporated into security inks and consumer products. In addition, microenvironment-specific changes in the emission properties of the LnNC tag were utilized to study and sense changes of physico-chemical parameters in different matrices. T2 - JCF Frühjahrssymposium 2023 CY - Gießen, Germany DA - 21.03.2023 KW - Lanthanide Nanocrystals KW - Anti-Counterfeiting KW - Fluorescence Spectroscopy PY - 2023 AN - OPUS4-59037 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -